


Good Boy

by Demon_Dark_Need



Series: SPN Kink Meme Fills [1]
Category: Supernatural
Genre: Age Difference, Anal Fingering, Anal Sex, Bestiality, Bottom Castiel, Cock Slut Castiel, Come Eating, Creampie, Crying, D/s undertones, Dubious Consent, Face-Fucking, Initial Dubious Consent, M/M, Manipulation, Praise Kink, Rimming, Size Difference, Smut, Submissive Castiel, Top Dean
Language: English
Status: Completed
Published: 2017-07-23
Updated: 2017-07-23
Packaged: 2018-12-05 22:21:16
Rating: Not Rated
Warnings: Underage
Chapters: 1
Words: 2,751
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11587335
Author URL: https://archiveofourown.org/users/Demon_Dark_Need/pseuds/Demon_Dark_Need
Summary: Dean has trained Castiel into his perfect little cockslut. Now he's going to put that training to the test.





	Good Boy

**Author's Note:**

> Read the tags and don't read if it's not your cuppa.
> 
> This was written for the [SPN Kink Meme](http://spnkink-meme.livejournal.com/) [prompt](http://spnkink-meme.livejournal.com/116307.html?thread=42367315#t42367315):
> 
> Dean, 25-35, is in a relationship with Cas, 13-15. It can be in a universe where relationships between adults and children are accepted, or it can be illegal and they have to hide it, I don't mind. One night Dean convinces Cas to let Dean's dog fuck him. Cas should be very reluctant, maybe even out right saying no at first (bestiality should definitely be illegal/taboo regardless of how relationships between adults and children are seen). He lets Dean talk him into it, though, and eventually starts getting into it. When the dog knots him he cries in pleasure-pain and comes untouched. Afterward, Dean cuddles and pets him and tells him how wonderful he was while Cas basks in Dean's praise (quite possibly why he agreed in the first place).
> 
> Not necessary but I would love if Dean's praise at the end was interspersed with some humiliation, like Dean telling Cas that it's okay that he's such a slut for dog cock, Dean thinks he's so pretty stretched around a knot like he's made for it, and he'll always let Cas get on his hands and knees for his dog. Also would love for Cas to start crying when the dog starts fucking him. Feel free to add other kinks as wanted!

Dean laced his fingers with Cas' and stretched the boy's arms over his head, pinning them to the bed.

"That's so good, baby. Keep your legs spread wide for me." Cas whimpered and pulled his knees farther back and Dean thrust in hard. "Yeah, baby, that's it, let me all the way in."

Dean let go of Cas' hands and sat back, resting his hands on Cas' narrow waist, enjoying how small Cas looked under him. He leaned his head back and held Cas still as he fucked into him, just enjoying how tight Cas was around him, the soft sounds that Cas made. Thinking about the blessing that was absent fathers and overworked mothers that allowed him to possess a treasure like Castiel. He'd finish fucking the boy and then send him back home, wet and open and aching, ready to be claimed again whenever Dean wanted.

"Shit," Dean moaned and wrapped his hand around Cas' dick. "Come on, baby, let me feel you come."

"Dean," Cas moaned, arching his back. "Please, please."

Cas had cried the first time Dean fucked him two years ago. Cas had only been twelve and Dean was more than twice his age, but now he was Dean's perfect little slut, spreading his legs and begging for it. Dean jacked him harder, wanting to feel Cas tighten around him as he came. Cas panted and moaned like the sweet little bitch he was.

"That's it; let me feel it baby." Cas' fists gathered up the sheets as his body went rigid under Dean as he came. "Yeah, sweetheart, that's so good."

Dean's free hand clamped down on Cas' waist as he stuttered to a halt, coming deep inside the sweet boy beneath him. He thrust slowly a few more times, milking himself.

"Cas, that's so good. You're so good for me. Your sweet ass is so fucking tight." He fucked Cas' tight little hole, listening to the squelch of his come as he kept fucking Cas. He let out shuddering moan and finally pulled out. He looked down at Cas' hole, which was gaping slightly. Come was leaking out of him and Dean used two fingers to scoop it up and brought them to Cas' mouth. "Open up, sweetheart."

Cas opened his mouth and Dean shoved his fingers inside. Cas moaned softly and sucked Dean's fingers, shivering slightly. Everything about him made Dean want to use him harder. He fucked his fingers in and out of Cas' mouth for a while before pulling them out.

"You were so good for me, Cas. Such a good boy." Cas whimpered as Dean kissed him and thrust his semi-hard dick back inside. Cas kept his legs spread wide and took what Dean gave him.

Dean finally pulled out and flopped back onto the bed next to Cas. He heaved several hard breaths and held out his arm when Cas turned into him to snuggle.

"Was I good?" Cas held Dean closer when he asked and Dean kissed his forehead.

"Yeah, babe, you were so good." He let his hand run down the boy's side, appreciating his leanness. "You've gotta get home soon."

Cas whimpered. "I want to stay."

"I know sweetie, but you have to go home."

"Can I come over tomorrow?"

"Nope, I've got people coming over. I'll text you, alright?"

Cas got out of bed and started to dress. "Okay."

_-~-_

Cas was hard already, on the floor, ass in the air, cheek pressed against the towel that Dean had laid down for him. Dean had spent a long time eating him out and fingering him open.

"You want to make me happy, don't you baby?" Dean asked and Cas nodded fervently.

"Yes, Dean. Yes."

Dean pushed three fingers back into Cas and hummed his appreciation. "Such a good little boy, right?"

"Yes, Dean," Cas moaned, pushing back on Dean's fingers.

Dean growled his approval and pulled his fingers out. "I want something, Cas."

"Anything," Cas breathed and Dean grinned. He spread Cas' ass cheeks apart and rubbed his thumbs over Cas' rim.

"Anything, sweetheart?"

Cas needed Dean like he needed air. He was the only one who paid attention to him, who said nice things to him. He would do absolutely anything for him. "Yes," he breathed.

"That's my good boy," Dean praised, running his fingers through Cas' hair. "So sweet for me, baby. Just hold still."

Dean kept his hand pressing down against Cas' head and whistled. Cas didn't understand what Dean was doing, but then he heard the jingle of a collar and nails on the hardwood floor. Dean pressed down harder on his head as Cas squirmed.

"Dean?"

That he still obviously had some faith in Dean made Dean's cock throb. Dean curled his hand in Cas' hair. "Yeah, baby?"

"Why..." Cas' voice broke and he swallowed. "What's Lynyrd doing here?"

"I want you to show me what a good boy you are," Dean murmured. "I want to watch him fuck you."

Cas jerked his head out from under Dean's hand and sat back on his haunches, protecting his ass from the dog. "You... what?"

Dean moved closed to Cas and put his hands on the boy's waist, his thumbs stroking the skin. "Yeah, baby. It would be so hot watching you get fucked by him. You'd look so good, Cas."

Cas was horrified by the suggestion, but Dean looked so eager. "But it's gross and... and... wrong."

"Come on, Cas, I wanna see it." He slid his hand around to Cas' lower back and pulled him forward to he could feel Dean's erection. Cas was totally soft. "Feel how turned on I am, sweetheart?"

Cas looked back at the dog, a large black lab, his lip pulling up in disgust. He couldn't imagine bending over and letting the dog mount him. He shivered in revulsion and looked back at Dean. "I don't want to, Dean. Please."

Dean frowned and sighed before pulling away. "I thought you said you'd do anything for me." He stood and stared down at Cas, shaking his head with disappointment. "Guess that's not true."

He turned away and Cas could feel anxiety squeezing his throat. What if Dean was so disappointed that he didn't want Cas anymore? What if he stopped calling Cas to come over? Cas didn't think he could live without Dean holding him and telling him he was good.

"You can get dressed and go home, Cas," Dean said, confirming all of Cas' fears.

"No," he said, his voice high and panicked. "Please, Dean." Cas didn't see Dean's little smile before he turned back to the boy, he just saw that Dean was still disappointed. "I can... I can do it.

He sort of felt like he was going to throw up, just contemplating it, but Dean's smile made Cas feel like he could breath again. He walked back to where Cas was still kneeling and brushed his fingers down Cas' cheek. "There's my good boy." He bent down and kissed the boy. "This is going to be so hot, baby. Bend back over." Cas closed his eyes and didn't move, so Dean wrapped his hand around the back of his neck and pushed. Cas whimpered softly and let himself be pushed down. He could do this for Dean.

He heard Dean moving around and then there were fingers wet with lube being pushed into him.

"Gotta make sure you're nice and wet. I don't want him to hurt you. I want you to enjoy this, baby."

Not a chance, Cas thought, but he forced himself to stay still.

"C'mere, boy," Dean said softly, and Lynyrd's collar jingled as he got up and came to Dean. Dean spread Cas' ass cheeks apart. "Here boy, look what I got for you. Take a taste of that sweet little ass."

Cas moaned miserably when he felt the dog's wet nose bump against his ass and then buried his face in his hands when the dog licked him. Oh god, this was so wrong, he didn't want this. He sobbed into his hands and Dean rubbed a hand up and down his back.

"Shh, you're doing so good, Cas. So good for me."

The dog kept licking him and Dean kept stroking his back, murmuring praise, and Cas couldn't stop crying. Then the dog's tongue went inside him and he yelped, utterly humiliated because that had felt good.

"Dean," he whispered, his voice tight with tears.

"Yeah, Cas. Feels good, doesn't it? Just wait 'til he's inside you, baby." Dean moved so he was by Cas' head and tugged on his hair. "Look up at me, Cas."

Cas shook his head, biting back a moan as the dog's tongue kept fucking into him.

"Yeah, baby, look up at me. Let me see those pretty blue eyes." When Cas still didn't move Dean pulled harder on his hair until Cas had to lift his head. "There's my beautiful boy." Dean swiped away the tears with his thumbs. "Feels good, doesn't it?"

Cas' face scrunched up as he started crying again and Dean tutted.

"It's okay to like it, Cas. I want you to like it." He looked away from Cas, back at the dog. "He's hard now, he's going to fuck you soon. His tongue's opening you up so good, isn't it? Do you like how it feels?" Cas looked away but Dean grabbed his chin and made him look back. "Does it feel good, baby?"

Cas choked down a sob and then nodded.

"Tell me, Cas."

Cas whined high in his throat, hating that Dean was making him admit it out loud. "Feels good."

"Say it all, baby."

"Dean," Cas sobbed. Fuck, the dog's tongue was reaching so far into him. "Please."

"Come on, sweetheart. It looks so fucking good, tell me how good it feels."

Cas panted for a moment, eyes closed, lost in the pleasure of it. "His tongue feels so good in my ass," he breathed finally, tears still coursing down his cheeks.

"I knew you'd like it. Your little ass is always so greedy to be filled up. Sweet little cock slut."

Cas moaned and dropped his head back down to the floor. He didn't want this to feel good, but it did, and he was craving something bigger. He wanted the dog to mount him, stuff his cock inside him and fuck him. He moaned again at the thought.

"That's it. So good, baby boy," Dean murmured.

When the dog stopped licking, Cas whined and spread his legs. He needed more, but then he felt the dog's claws scraping across his back before finding purchase on his hips, and the hot poke of his dick against his ass. He shifted, trying to get the dog into the right place, and then suddenly he was full.

He cried out it pain, stretched wide so suddenly, and then again because the dog was thrusting hard and fast into him.

"Oh, fuck," he groaned. Jesus, he hadn't thought it would be like this, so rough and hard. "Dean."

"Jesus baby, you should see yourself. You look so small under him and he's fucking you so hard. Fuck."

Cas looked up and saw that Dean had opened his pants and pulled his cock out, was stroking it hard and fast as he watched Cas get fucked by the dog.

"How does it feel, Cas? How does it feel having that dog cock split you open, baby?"

"So good, Dean. Oh god, so fucking good." His fingers clawed at the floor, trying to brace himself against the dog's powerful thrusts.

"So fucking hot." Dean knee walked closer to Cas' face and lifted his head. Cas took the hint and opened his mouth so Dean could shove himself down Cas' throat. "Look at you, Cas, fucking spit-roasted between me and my dog. And Jesus, you're so hungry for it. Look how fucking hard you are, your sweet little cock, drooling precum."

Cas was mortified to realize that Dean was right, his cock was hard and swinging below him in time with the dog's thrusts. He was getting off on being fucked by Dean's dog. He was so twisted.

"Don't cry, baby. You look so good like this, gagging on my cock, ass spread open by my dog. Fuck, I'm not gonna last long."

Cas felt the same. He could feel his balls tightening because he was getting off being fucked by a dog. And Dean was loving watching it. He was fucking Cas' throat hard and deep, both hands holding the back of Cas' head as he thrust in. Cas finally just let himself relax into what was happening, let Dean's excitement make all of this okay. The dog fucking into him in hard, quick jabs felt so fucking good and if he could get just a little bit more, he'd be coming.

Dean pushed his cock down Cas' throat and stayed there, cutting off Cas' air. He'd done it before and each time it had made Cas come so hard. This time, combined with the dog fucking into him from behind he felt like he was going to fucking explode.

Dean thrust into his throat a few more times and then came with a long groan.

"Fuck baby, eat it. Gonna fill you up with come from both ends."

Cas swallowed convulsively, feeling so fucking blissed out. Dean was choking him, which he always loved, and his ass was still getting pounded, which felt so good. Getting both at the same time was steadily driving him to the edge. He whimpered as Dean pulled out of his mouth and Dean ran his hands through his hair and over his shoulders in comfort.

"It's okay, baby, you're okay."

"Dean," Cas plead. "Please touch me. I need to come. Please, fuck."

Dean had slumped back onto his elbows, watching Cas still taking the dog pounding into him.

"Shit, Cas. You look so fucking hot taking his dick."

Cas arched his back and gasped when the dog's cock slipped a little deeper inside him. "Fuuuuck," he moaned.

"Come on baby, are you gonna come for him? You've never come on my dick alone, are you gonna come for a fucking dog like you never come for me?""You can, baby," Dean encouraged. "He's about to knot you and you're gonna fucking love it."

Cas arched his back. He didn't know what Dean meant by knot, but he was so fucking close to coming. He just needed a little more. He didn't know what it was, but he thrust back against the dog, spread his knees farther apart. He could feel something nudging against his hole and then, suddenly, something big and hard pushed inside him, spreading and holding him open. He cried out in pain at the same time his whole body convulsed in pleasure. His cock bounced as he came, untouched, the dog's knot still jerking inside him.

Cas moaned in a combination of pleasure and pain as the dog got off him and turned so they were ass to ass. It caused the knot to pull on his abused rim and he shivered as his cock gave a last twitch.

"God dammit, Cas," Dean breathed as he sat back. "You took that like a bitch in heat."

Cas flushed and looked down. Now that he'd come he was feeling the humiliation of the situation again.

"No, no, it's okay, baby. I loved watching you take it and you still look so good, hanging on his knot. Feels good, doesn't it?"

Cas nodded, because it did. It ached, just on the verge of pain, but that just made it feel better.

"Come on, Cas, you know I wanna hear you say it."

Cas licked his lips. "His knot feels good in my ass," he admitted.

"Yeah, baby. Such a slut for it. You gonna beg for it to happen again? Beg to be my dog's bitch?" Cas whimpered and Dean bent down to kiss his shoulder. "It's okay, Cas. You were so good and I want to watch you take it again. I wonder if we could arrange you so he could fuck you while you're on your back. I'd love to see your legs spread open as he pounds you."

Cas groaned again and Dean chuckled. "I knew you'd like that idea. You love having your legs spread while I fuck you." He ran his hand through Cas' hair again. "So good, Cas. You're my good boy."


End file.
